The present invention relates generally to the working of cement.
It has heretofore been generally known, as exemplified by U.S. Pat. No. 2,887,934, to provide cement finishing machines of the type which employs two rotors having radiating troweling blades, the blades of the two rotors being so related and operated that the reaction forces between the blades and the cement are cancelled out. In this known embodiment, a guiding handle, centrally attached to the machine frame, provides for manually and rather laboriously pulling the machine in a forward or generally forward direction during the troweling operation. The controls mounted on the handle were also provided for simultaneously varying the tilt angle of the troweling blades carried by the two rotors.
It has also been known to provide ride-on troweling machines of the type having two sets of troweling blades, in which the blade sets are relatively tiltable by means of a rider rotatable steering handle to control the direction of travel by reactive forces generated between the blades and the cement. Due to the operating characteristics of this type of machine, it is not possible to utilize a meshed arrangement of the blades of the adjacent sets of troweling blades to provide intersecting circular troweling areas. As a consequences the line of movement of the machine must be carefully maintained at an angle to the longitudinal frame axis, in order to avoid producing untroweled areas between the troweling blade sets.
The troweling machine of the present invention is a radical departure from the operative concepts, as known from the above noted Patent and ride-on machines and provides a unique arrangement for utilizing the reactive forces between the blades and the cement to generate controllable propelling forces that may be selectively utilized to self-propel the troweling machine in either a forward or reverse direction and wherein the handle is positioned at one end of the machine frame structure, and enables manual lateral movements of the machine with respect to its propelled direction of travel.
The invention also is unique in that it not only provides an arrangement in which the direction of travel may be controlled by raising and lowering movements of the handle, but also provides remote control members on the guiding handle for regulating and adjusting the reactive propelling forces, as well as for independently adjusting and simultaneously varying the tilt angle of the troweling blades of the respective rotors.